Excuse my ignorance Poison Ivy, and possible sarcasm but I assure you it will be the same as any other shopping mega-arcade in the UK.
You will go to the shops you are familaiar with.
The car park will be confusing.
The security guards will have hideous uniforms.
There will be single mums and prams galore.
There will be hideous displays of cheap tack in the central corridors.
There will be chavs by the entrance smoking.
There will be old women smelling of piddle getting in your way.
There will be tarts who work on the perfume counter walking around thinking they are the bees knees when in reality they are on the minimum wage and live with mummy and daddy.
The smaller chains will be owned by muslims who send all the profits back home to fund terrorism and child abuse.
You will spend money you do not have on things you do not want.
Poison, coming from Southend I have actually been. Its one of the few shopping centres with the posher designer shops so you get the WAGs and Jodie Marsh going there (don't let that put you off!). If you want a place with more High Street-type shops then you're better off at Lakeside, its only about 10 mins drive from Bluewater, just over the Dartford bridge.
Poison Ivy - Bluewater is great! Lakeside is also good (Bluewater has more designer - Lakeside just high street) and opens until 10 p.m. during the week so is really peaceful if you nip there at say 7 pm. on a Tuesday evening or something).... The one thing I would point out is on the weeked Bluewater gets really really packed. To the point where you see cars parked in the car park randomly because there are not spaces. When I go on a Saturday I go for when the shops open and make sure I leave by 1.00 p.m. otherwise I go from being 'Great' to 'Hate' (like what I did with the use of words rhyming there?!!)